Pseudo spin-orbit coupling of Dirac particles in graphene spintronics

TL;DR

This paper explores the pseudo spin-orbit coupling effects in graphene's Dirac particles, proposing an artificial structure to generate strong pseudo SO fields for potential spintronics applications.

Contribution

It introduces a novel artificial structure with a graphene ring and charged nanodot to induce large pseudo SO coupling, surpassing conventional Rashba effects.

Findings

Large pseudo SO coupling achievable in proposed structure

Potential for pseudo spin relaxation and switching applications

Theoretical feasibility demonstrated

Abstract

We study the pseudo spin-orbital (SO) effects experienced by massive Dirac particles in graphene, which can potentially be of a larger magnitude compared to the conventional Rashba SO effects experienced by particles in a 2DEG semiconductor heterostructure. In order to generate a uniform vertical pseudo SO field, we propose an artificial atomic structure, consisting of a graphene ring and a charged nanodot at the center which produces a large radial electric field. In this structure, a large pseudo SO coupling strength can be achieved by accelerating the Dirac particles around the ring, due to the small energy gap in graphene and the large radial electric field emanating from the charged nanodot. We discuss the theoretical possibility of harnessing the pseudo SO effects in mesoscopic applications, e.g. pseudo spin relaxation and switching.